Brown pelicans staying south: Anchovy abundance off Central Coast may be the cause

A lack of sardines and an abundance of anchovies may have caused fewer brown pelicans to migrate to the northwest U.S. coast this past summer and fall, according to several wildlife and environmental biologists.

Laird Henckel, an environmental scientist for the California Department of Fish and Wildlife, said the pelicans that would have normally migrated as far north as British Columbia decided to stick around the Central Coast, where an anchovy smorgasbord is taking place.

"Right now we're seeing unprecedented amounts of brown pelicans in the Monterey Bay area," Henckel said. "They may not show up north as much as they have in the past because there is so much food down here."

Wildlife biologist Deborah Jaques of Pacific Eco Logic in Astoria, Oregon has conducted surveys on the pelicans from Northern California to Washington since 2008. Her most recent survey showed a drop in visitations.

"Not as many birds flew north this year," Jaques said.

Brown pelican abundance on the northwest coast has been decreasing over the last decade, according to director Sharnelle Fee of the Wildlife Center of the North Coast in Astoria, Ore.

"This year a survey showed the lowest count since 2003 for them even coming up," Fee said. "This was really an off year."

The referred survey was conducted this September by the Oregon Coast National Wildlife Refuge on brown pelicans living on the northwest Oregon coast. Only 7,018 birds were recorded during the survey, or half the average for the last decade, according to Fee.

Jaques said she does not know what is directly causing the decline because of a lack of adequate coastal surveying and government funding on both the birds and their prey. Since the pelicans were removed from the Endangered Species list in 2009, she said monitoring has been poor.

"Without data, you don't have a lot to go on," Jaques said. "It's hard to explain when things happen when you only have a small amount of data. That's not good management."

A five-year-status review of the pelicans required by the Endangered Species Act is set to take place in 2014.

The large quantity of anchovies in Monterey Bay may have helped the pelicans avoid another year of starvation that has been affecting the birds for the past three years, Jaques said.

"Breeding success on the Channel Islands was really poor for the last three years," Jaques said. "There has been higher mortality than usual over the last five years."

For reasons unknown, Jaques said many pelicans have been overwintering in the north during the last several years instead of migrating back south around November as is expected.

Henckel said the pelicans may have stayed up north due to a lack of food off of the California coastline.

"In 2011 and 2012, the pelicans got up there and ran out of food," Henckel said. "They were starving and scavenging for food at fish cleaning stations. A lot of them got covered in fish oil and died from hypothermia."

During this three year period, brown pelicans were reported to have been killing murre chicks for food and scavenging from fishing docks.

A recent decline in Pacific sardine fisheries this year may lead to even more problems in the future, according to fishery policy analyst Josh Lindsay of the National Marine Fisheries Services

"We saw a pretty large drop of the biomass from last year to this year," Lindsay said. "We see huge fluctuations and substantial variations from year to year, but the stock has been declining over the past three years."

In response to the decline, the Pacific Fishery Management Council voted in early November to lower catch limits of Pacific sardines during the first four months of the 2014 to 6,946 tons -- about one-third of the limit for set in 2013.

Lindsay said his department will be doing a new stock assessment on the sardines for the July 2014 to June 2015 season.

"It's something we're trying to understand," Lindsay said. "No overfishing has occurred in recent years. It's likely to be something linked to temperature."

Because pelicans rely on sardines as food when they return to their southern nesting grounds during the summer, Jaques said the decline could have detrimental effects.

"If their food isn't there in the breeding colonies where they need it, they will fail," Jaques said. "Patterns are changing, and I believe the pelicans are responding to these large scale changes."

Henckel said that brown pelicans "should be all right for now" as they remain in the Central Coast.

Professor Mark Colwell of the Wildlife Department at Humboldt State University said that if the sardine fisheries continue to decline, it will significantly impact pelicans during their nesting season and in turn, the numbers that migrate to Humboldt Bay.

"If the sardine crash persists, the birds may not have enough energy necessary to breed, or they may have reproductive failure," Colwell said. "As the population goes, so do the local numbers here."